How can I prevent oxygen or pH microsensors from breaking when measuring profiles across tissue?

For the insertion of microsensors by PreSens in tissues (here it is a sugar snap pea) it is sensible to use a manual micromanipulator for measuring profiles.

It is recommended to use the Manual Micromanipulator for inserting fiber optic microsensors into tissue and measure profiles. The microsensor is driven into the tissue by the micromanipulator in μm steps. (It is impossible to be accurate, when inserting the microsensor by hand, and any movement or wedging might break the sensor tip.)Please make sure the microsensor is paused for about 10 seconds at each desired measurement point to allow the sensor to equilibrate and to obtain accurate measurements.